1. FIELD OF THE INVENTION
This invention relates to a pulling device, and in particular to a device for removing a key from a railway car coupler.
2. DISCUSSION OF THE PRIOR ART
The removal of so-called E-type coupler draft keys used on railway cars is very difficult, usually involving the use of one key for driving a second key out of the latched position. The result is often that the first key becomes lodged and is difficult to remove. A search for a solution to the above problem led to the present invention, the object of which is to provide a relatively simple device for removing a coupler draft key from a railway car coupler which is easy to connect to the key.
Fluid actuated cylinders previously have been used in pulling devices. Examples of such devices are described in U.S. Pat. Nos. 2,452,457, issued to G. W. Gary et al on Oct. 26, 1948; 2,570,914, issued to C. N. Buck on Oct. 9, 1951; 2,735,649, issued to S. A. Swallert on Feb. 21, 1956; 2,874,933, issued to J. E. Feucht on Feb. 24, 1959, and 3,066,913, issued to A. E. Leeson on Dec. 4, 1962. To applicant's knowledge, the above listed patents represent the most relevant prior art. While some of the patented devices have features in common with the invention described herein, none of them offers the elegantly simple solution to the problem solved by the present invention.